Laboratory Evaluation of Two Commercial Abamectin-Based Insecticides Against Anastrepha ludens (Diptera: Tephritidae): Lethal and Sublethal Effects

Toxic environmental effects of most insecticides have led to a search for bio-organic insecticides. In this study, we tested the effects of lethal and sublethal exposure to two abamectin-based insecticides (VOLIAM TARGO and LUQ-THOR) on survival, mating, and oviposition of the tephritid Anastrepha ludens (Loew). Different doses of insecticides (0.001-2.00% of the commercial products) were offered mixed with the phagostimulant bait Captor commonly used in spraying and in trapping activities for the control of flies. Both insecticides exhibited 90% killing effectiveness (Abbott index) when offered in doses between 0.02 to 2.00%. The LC50 obtained from the bioassay at 72 h after treatment was 0.003% of commercial product for TARGO and 0.008% for LUQ-THOR. Sublethal exposures to insecticides (0.003%; LC50 for TARGO and LC30 for LUQ-THOR) caused a reduction in oviposition but not in mating parameters, indicating that females were more susceptible than males to reduced doses of insecticide. The mean amount of eggs deposited 5 d after feeding on the insecticide-bait mixtures was reduced up to a third compared with the amount of eggs deposited by untreated females. Both insecticides are promising bio-organic alternatives to malathion in bait control programs against A. ludens.